The next 8.1-billion-euro tranche of aid for Greece could be paid in several instalments, the EU's top economic official said on Friday.

"It is possible, but not certain. It all depends on whether Greece can meet all requirements that they are committed to," EU Economic and Monetary Affairs Commissioner Olli Rehn told a seminar in his hometown of Mikkeli.

Greece is hoping to reach a deal with its lenders to free up the next tranche of bailout cash by Monday. Its lenders have threatened to freeze the payment if Greece falls behind on reforms.

"Talks are continuing and they will continue as long as needed," Rehn said.